Enhanced vertex pinning in annealed TlBa/sub 2/CaCu/sub 2/O/sub x/ thin films

Author

Venturini, E.L. ; Newcomer, P.P. ; Siegal, M.P. ; Overmyer, D.L.

Author_Institution

Sandia Nat. Labs., Albuquerque, NM, USA

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

1592

Lastpage

1595

Abstract

Furnace anneals of TlBa/sub 2/CaCu/sub 2/O/sub x/ thin films at temperatures above 500/spl deg/C cause partial TlO/sub x/ loss. High resolution transmission electron microscopy images reveal nanometer-scale discontinuities (pinched stacking faults) in the microstructure of annealed films. Significant increases in the vortex pinning potential and critical current density at elevated temperatures in strong magnetic fields are observed and are attributed to the presence of these localized defects.

Keywords

barium compounds; calcium compounds; critical current density (superconductivity); defect states; flux pinning; high-temperature superconductors; localised states; superconducting thin films; thallium compounds; 500 C; TlBa/sub 2/CaCu/sub 2/O; annealed TlBa/sub 2/CaCu/sub 2/O/sub x/ thin films; critical current density; enhanced vertex pinning; furnace anneals; high resolution transmission electron microscopy; high temperature superconductor; localized defects; nanometer-scale discontinuities; partial TlO/sub x/ loss; pinched stacking faults; vortex pinning potential; Annealing; Critical current density; Furnaces; Image resolution; Magnetic films; Microstructure; Stacking; Temperature; Transistors; Transmission electron microscopy;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.620880

Filename

620880